Application of soil washing process for the remediation of heavy metal contaminated soil around the Jang Hang smelter
- Abstract
- The Jang Hang smelter is well known as a serious heavy metal contaminated area in Korea. The aim of this study is to demonstrate the feasibility of the soil washing process applying to the soil around the Jang Hang smelter, having high concentrations of heavy metals. The soil was sampled from 7 sites (S1 ~ S7) around the Jang Hang smelter for the washing experiments to investigate the heavy metal removal of the soil washing. Batch experiments were performed at the different ratio of soil to washing solution, different washing time, various kinds of washing solutions and different pH condition to determine the optimal soil washing condition. Heavy metal concentration of S4 soil was the highest among soil samples, suggesting that S4 soil was contaminated with copper, lead and arsenic. The concentrations of copper, lead and arsenic were determined to 2,666.8 mg/kg, 1,229.9 mg/kg, and 248.6 mg/kg, respectively. In this study, the S4 soil of which size was larger than 297 µm in diameter was chosen for the batch experiments because coarse grained particles (>297 µm) showed high concentration of heavy metals and also covered more than 95 % of total soil particles.
Results of washing experiment using various pH conditions suggested that copper and lead removal efficiencies for pH 1 solution were 14 % and 7 %. From the results of batch experiments, the removal efficiencies of arsenic and copper for the soil washing was 92 % and 93 % respectively, when 0.5 M of NaOH solution was used at 1:3 ratio of soil to solution for 1 hour washing. The removal efficiencies of copper and lead were 51 % and 68 %, respectively, with 0.5 M of HNO3 solution at 1:5 ratio of soil to solution for 30 minute washing. The removal efficiency of arsenic was 41 % with 0.5 M of HNO3 solution at 1:3 ratio of soil to solution for 30 minute washing. When the washing condition was 1:3 ratio of soil to 0.5 M of HCl solution, copper and lead removal efficiencies were determined as 46 % and 56 %, respectively. In the case of arsenic, the removal efficiency by using 0.5 M of HCl washing solution was 51 % at 1:5 ratio of soil to solution for 30 minute washing.
Because the removal efficiencies of heavy metals for one time washing did not reach the remediation goal (KPWL: Korea pollution warning limit), six consecutive soil washing were performed to satisfy the remediation goal.The accumulative removal efficiency for 0.5 M of HNO3 (or HCl) solution every washing time was investigated. The accumulative removal efficiency of copper was 97 % after the 5th washing with HNO3 solution. The accumulative removal efficiency of lead was higher the remediation goal after the 2nd washing with HNO3 and HCl solutions 1:1 and 1:3 ratio of soil to solution. The removal efficiency of arsenic was over than 100 % after the 4th washing with HCl solution at 1:5 ratio of soil to solution.
The finally, based on the all results and the properties of the soil, the optimal soil washing condition was suggested to remove heavy metals from soil around of the Jang Hang smelter. It was 1:3 ratio of soil to 0.1 M of NaOH solution for 1 hour.
Key words: Jang Hang smelter, heavy metal contamination, soil washing process
- Issued Date
- 2014
- Awarded Date
- 2014. 8
- Type
- Dissertation
- Publisher
- 뷰경대
- Affiliation
- 대학원
- Department
- 대학원 지구환경과학과
- Advisor
- Prof. Minhee Lee
- Table Of Contents
- List of Figures v
List of Tables vii
Abstract viii
Chapter 1. Introduction 1
Chapter 2. Objective 2
Chapter 3. Background 3
3.1. Outline of research area 3
3.1.1 Research area 3
3.1.2. Geological characteristics 4
3.2. Heavy metal contamination in soil 6
3.2.1. Arsenic 7
3.2.2. Lead 8
3.2.3. Copper 9
3.2.4 Cadmium 11
3.3. Soil washing process 13
3.3.1. Principle of soil washing 14
3.4. Description of soil washing process applied in this study 16
Chapter 4. Experimental methods 17
4.1. Material for the experiment 17
4.1.1. Soil sampling and analysis for heavy metal concentration 17
4.2. Batch experiments 19
4.2.1. Measurement of soil properties 19
4.2.2. Determination of cut off size for the soil washing 19
4.2.3. Batch experiment with various pH of washing solution 21
4.2.4. The calculation of remediation goal for each heavy metals 22
4.2.5. Batch experiments with various washing solution having different concentration 23
Chapter 5. Results and Discussion 25
5.1. Result of soil characterization 25
5.1.1. Heavy metal concentration and pH of soil 25
5.1.2. Physicochemical properties of soil 27
5.1.3 Determination of the cut-off size for the soil washing 29
5.2. Results of batch experiment 32
5.2.1. Batch experiments for soil washing with various pH conditions 32
5.2.2. Batch experiments with various washing solution 33
5.2.2.1. Batch experiment with HNO3 solution 33
5.2.2.2. Batch experiments with HCl solution 36
5.2.2.3. Batch experiments with H2SO4 solution 39
5.2.2.4. Batch experiment with NaOH solution 42
5.2.3. Batch experiments with the repeated washing 46
5.2.3.1. Copper, lead and arsenic removal efficiencies with HNO3 solution 46
5.2.3.2. Copper, lead and arsenic removal efficiencies with HCl solution 49
Chapter 6. Conclusion 52
References 55
- Degree
- Master
- Files in This Item:
-
-
Download
Application of soil washing process for the remediation of heavy metal contaminated soil around the.pdf
기타 데이터 / 1.59 MB / Adobe PDF
-
Items in Repository are protected by copyright, with all rights reserved, unless otherwise indicated.